PROBLEM TO BE SOLVED: To provide a titanium alloy rod for spinal fixation capable of achieving both high strength and low rigidity at a higher level. SOLUTION: Nb: 25 to 37% by mass, Ta: Nb + 0.8Ta, 36 to 45% by mass, Zr: 2 to 6% by mass, O: 0 to 1.0% by mass, the balance is Ti and unavoidable impurities. A titanium alloy rod (10) for spinal fixation having a first region (11) in which the α phase is precipitated in the β phase and a second region (12) composed of the β phase. [Selection diagram] Fig. 1【課題】高強度と低剛性をより高いレベルで両立できる脊椎固定用チタン合金ロッドを提供する。【解決手段】Ｎｂ：２５～３７質量％、Ｔａ：Ｎｂ＋０．８Ｔａで３６～４５質量％、Ｚｒ：２～６質量％、Ｏ：０～１．０質量％、残部がＴｉと不可避的不純物からなり、β相中にα相が析出した第１領域（１１）と、β相からなる第２領域（１２）とを有する脊椎固定用チタン合金ロッド（１０）。【選択図】図１
